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On-Board Sanding Systems

I'm trying to research how common on-board sanders are, but haven't found much stats or regulations. Anyone knows if there are any regulations/standards that require them? Or if there isn't any, how common are they?

G'day Justin,
If you are still around since your post, I cannot answer for UK motive power.
But, here in Australia, locomotives possess sanding equipment for traction purposes.
EMU and DMU commuter trains generally do not possess any sanding equipment.
However, the QR 2000 class rail motors did possess sanding equipment.
Since the 3801 Cowan bank incident, De-sanding equipment must be applied to all locomotives.
Air tubes blow deposited sand from the rails behind each traction wheel.
This is to prevent track circuited automatic signals from displaying clear behind a train.
Sand build up on the rail head can insulate the wheels from the track circuits.
If a locomotive deposits sand uncontrolled, Train Control must be notified and Absolute Block Working instituted.
Steve.

I'm trying to research how common on-board sanders are, but haven't found much stats or regulations. Anyone knows if there are any regulations/standards that require them? Or if there isn't any, how common are they?

In the UK, almost all traction units (ie, locos and multiple units) have sanders. Our 'green and pleasant land' means that stopping and pulling away in the leaf-fall season can be extremely tricky on occasions. A steel wheel on a steel rail, with a layer of vegetable oil in between means that there can be little or no adhesion sometimes.

Modern units may have a combination of;
1) Autosanders which lay fine sand under the powered wheels whenever the Wheel Slip/Slide Protection system detects that the train is struggling, and
2) A Manual sanding button which allows the driver to lay sand even though the train doesn't think there's a problem (if all the wheels are locked, the WSP system may think the train has stopped !), or increase the rate of sanding if the autosander is already deployed. This button is also known affectionately as the 'brown trouser' or 'sphincter' button. I'm sure you can work out why.

Additionally there are automatic sandite applicators at various points on the line where there is an area of known low adhesion, and the RHTT (Rail Head Treatment Train) runs across the network using a high pressure jet of water to clean the railhead.

As aussiesteve points out above, drivers are required not to lay sand over points or crossings because it can bung them up, and there is a risk that the build-up of sand may isolate a train from the track circuits and make the train disappear from the signalling system !

However if your train is running away, and they do, you will chuck every grain of sand down regardless.